However, one new royal family member was noticeably missing from the Buckingham Palace balcony line up.
Archie Harrison Mountbatten-Windsor, the son of Prince Harry and Meghan Markle, was nowhere to be seen, much to the annoyance of royal fans, who are now calling out the Queen for snubbing Baby Archie.
WATCH: British royal family are all smiles during Trooping the Colour ceremony
Furious fans have questioned whether the Queen banned Archie Harrison from her official birthday celebration because he was too young.
Baby Archie was born on May 6, so he was just over one month old on the day of the Trooping the Colour parade.
But there's no hard and fast rules surrounding when a royal can debut at the event, as the Queen herself has proved in the past.
In fact, in 1964 Queen Elizabeth and Prince Philip took their then three-month-old son, Prince Edward, out onto the Palace balcony at that year's Trooping the Colour event.
Which is something that hasn't passed royal experts by, as editor of Majesty magazine Ingrid Seward told Fabulous Digital: “The Queen, through her private secretary, could easily have said Archie was far too young for the Palace balcony, which indeed he is.
“She herself took baby Prince Edward onto the balcony in June 1964 but he was three months old and she was the Queen so she could do as she liked!"
While Queen Elizabeth does make the rules, it's unlikely that she would want very young babies on the balcony.
“The last thing she wants is for millions of TV viewers to witness a childhood tantrum,” Ingrid added.
A just over one year old, Prince Louis, the youngest child of Prince William and Kate Middleton, made his debut at this year's event. He was joined by his brother Prince George, 5, and sister Princess Charlotte, 4.
Meghan Markle, Duchess of Sussex also made a surprise appearance at the celebration. The Duchess is currently on maternity leave and taking a break from her royal duties.